#include<iostream>  
#include<string.h>
using namespace std;
 char *   strCat(char *  Dest,const char * Source){
 	int destLength=0;
 	int sourceLength=0;
 	char*dest=Dest;
 	const char*source=Source;
 	while(*(dest++)!=0)
 	 destLength++;
 	while(*(source++)!=0)
 	 sourceLength++;
 	char*newchars=new char[destLength+sourceLength+1];
	 newchars[destLength+sourceLength]='\0';
	 source=Source;
	 strcpy(newchars,Dest);
	 while(*(source)!=0){
	 	*(newchars+destLength++)=*(source++);
	 }
	 *(newchars+destLength)='\0';
	 return newchars;
 }
 int main(){
 	cout<<strCat("hello"," world!");
 }
